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First you need to know how to convert psi (Pound per Square inch) to Bars. 1 Bar = 14.5 psi. So if you are reading 48 psi at the low side, it is 48/14.5 = 3.3 Bars. 250 psi at the high side is 250/14.5 = 17.2 Bars.

This is what you tell me what you read with your gauges.

Now find the graphs for the 210.055 chassis (this is 1997 E320 which has the same a/c system as your car) which are the right column of graphs. Then if the ambient temperature is 25 degrees C, find 25 degrees C in the horizontal line (x or abscissa plane), and draw a vertical line over all 4 graphs, and note the values in the vertical lines.

I read

4-6 degrees C for the air temp from the center vent
1.8 Bars for the low side pressure
10-14 Bars of High side pressure
94 degrees C for the refrigerant temperature.

So if you are reading 3.3 Bars at the low side, it is 3.3 - 1.8 = 1.5 Bars higher than what it should be. 1.8 Bars is around 26 psi, and you are reading 48 psi.

So you have a high low pressure side problem. If you look at the interpretations, it could be a bad compressor, or a continuously open expansion valve. For the latter, you get ice cold air coming from the vents first, then it will get warmer and warmer, as the low side pressure starts building up. Sometimes a defective expansion valve will cause the compressor valve to go bad, as when you have more refrigerant in the liquid form at the low side, and the compressors do not like to compress refrigerants in liquid form.

Regarding the line blockage, over time, you get crud in the system, especially if you introduce moisture, air when you charge the system up (without purging the charge hoses of moist air). With refrigerant, oil and water and other contaminants, you will have a plugged up receiver / drier and partially clogged condenser. This will increase the high side pressure, as the flow is restricted. This is one of the problems of relying on the pressure gauge of the climate control system which reads the pressure after the drier, not before. So if the drier is plugged up and restricting flow, the gauge will always read less pressure than the actual gauge pressure at the high side valve. This is why it is important to use gauges, instead of completely relying on climate control system readings.
Matt,
I get it now:( Ambient at 25 C approx 80% RH)
Center air outlet temp is much higher than the 5-7 C expected(41 F)
Clearly I have 1 BAR higher pressure on the LO side.
HI pressure is also higher than expected at around 210.
Not sure what the refrigerant temp is -- I guess I can read from the diagnostics.

Based on this I definitely need a new compressor and as you have suggested, and I may as well replace some of the other components as you have also suggested.
Now I need to assess if I can do these by myself, through some DIY.
 

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I'm still learning the new control panel options but grew weary of the pissing contest and opted simply to delete the most recent which really didn't seem constructive to the problem solving. Please refrain from the public pissing. Take it private (now called 'conversation'). Not everyone is as smart as you or your ego believes so I ask for a little patience and civility, please. Take a breath.

The forum exist to encourage problem solving.

p.s. Don't forget that you can elect to suppress a member's response simply by using the IGNORE feature in your ACCOUNT SETTINGS. type in the member's name and their posts will be masked whenever you logon to Benzworld (with option to peek if you can't resist). It's a good blood pressure attenuator ;)

update: oops, the new site changes also changed the IGNORE feature. now, you simply left-click the offending member's icon and a subpanel will pop up which includes the IGNORE toggle.
 

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You did that before Raymond and it did not change anything.
When you "swept under the carpet" 5 replies who actually could bring some resolution, we still have hundreds if not thousands chaos-creating replies on the forum
If that is how you want to run the forum , I leave it at this point.
 

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Had the discussion stayed with on a technical path I would have kept my mitts off. Once the lobbing of insults began and finger pointing based on behavior, I felt the discussion deteriorated, creating the 'chaos' which was no longer helpful. So.... baby+bathwater = tossed.
 

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Thank you Raymond for your assistance in keeping the forum civil. There is a big difference between expressing an opinion, and forcing an opinion with an insulting language.
 

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Point is that discussion went off technical path long time ago.
That used to be great tread and Matt was great contributor here, now it all diverts into something I can't even name.
Plutoe was doing the same on this forum and he was stopped.
IMHO we don't deserve that.
 

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Well, I am done with this thread. I helped DilSingh as far as I could, and if he needs any help from me, he can always PM me. If he needs / wants help from Kajtek1, I am sure he would help him out.
And
Pip pip tally-ho ! :)
 

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Well, I am done with this thread. I helped DilSingh as far as I could, and if he needs any help from me, he can always PM me. If he needs / wants help from Kajtek1, I am sure he would help him out.
And
Pip pip tally-ho ! :)
Thanks Matt. I appreciate your help. I do have all the instructions I need to do this job.
I really do have a Ph D from England -- earned not honorary! -- its in Computer Architecture.

Most of the time, I do these jobs on the car as a learning exercise as well as the satisfaction of DIY.

Kajtek1, I have seen many great contributions from you. There is and never was any intention of ignoring your instructions or upsetting you.

Getting back to the problem, after clearing the error codes I got error code Eb1416, however I checked the re-circulation pump by connecting directly to another battery and it works fine, The hoses connected to it are also not blocked, Not sure why the error code is set or if its related to the problem ?
 

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You can ignore coolant aux pump for AC troubleshooting. Most likely motor brushes wear out and they will be intermittent for some time before permanent dead.
I am gifted with extreme patience, so I am not getting upset in the first place and it is not members who ask endless question, while not following the procedure that are the issue. Few years ago, great forum contributor - Greg aka Check Codes made great topic how new members go sideways with their replies, while ignoring all common sense. Seems we lost subscriptions with new script, so can't find the link, but it is whole book on its own.
If you scroll via AC topics in this section, you will find several of them with pages and pages of replies and no real help given.
Some kind of forum phobia, that you got sweeped into?
Anyway, if you want your problem properly troubleshoot, start new topic and make sure you have 2 sets of sensor readouts.
1 for calibration, taken on cold car in the morning before engine starty
2. for performance taken a minute after restarting car who seat on hot parking lot.
Also observe pressure #7 after restarting hot car.
Your manifold gauges show poor calibration per your report as well, but that would be another story.
Also from what I remember - UK switched to metric system about 40 years ago?
 

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You can ignore coolant aux pump for AC troubleshooting. Most likely motor brushes wear out and they will be intermittent for some time before permanent dead.
I am gifted with extreme patience, so I am not getting upset in the first place and it is not members who ask endless question, while not following the procedure that are the issue. Few years ago, great forum contributor - Greg aka Check Codes made great topic how new members go sideways with their replies, while ignoring all common sense. Seems we lost subscriptions with new script, so can't find the link, but it is whole book on its own.
If you scroll via AC topics in this section, you will find several of them with pages and pages of replies and no real help given.
Some kind of forum phobia, that you got sweeped into?
Anyway, if you want your problem properly troubleshoot, start new topic and make sure you have 2 sets of sensor readouts.
1 for calibration, taken on cold car in the morning before engine starty
2. for performance taken a minute after restarting car who seat on hot parking lot.
Also observe pressure #7 after restarting hot car.
Your manifold gauges show poor calibration per your report as well, but that would be another story.
Also from what I remember - UK switched to metric system about 40 years ago?
Ok, I will start another thread and post the measurements you suggested,

Europe did switch to the metric system a long time ago and the French and Germans complied quickly; the British are a stubborn lot who follow the imperial and metric system simultaneously.. Its the reason why tire pressure is still in PSI, Pounds and pence exist at the same time as Euros etc.
Converting from BARS to PSI and vice versa is easy these days, given Google as is F to C and vice versa. However, once you start thinking in PSI or degrees F, it hard to switch quickly as it just does not seem "normal".
The gauges I used were from a Tool rental place and I had no real way to either do the:) calibration or suspect that it was needed.
2602252

I guess I was looking for simple answers to a complex problem hoping to leverage other people's experience.
 

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Yeah, I thought that earlier today (thread too lengthy and lot of scattered thoughts over time - it's almost been a decade and folks aren't really likely to plow through hundreds of posts which make up this thread. Thanks for sticking with this latest problem, dilsingh and Kajtek1
 
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